If you have been browsing lighting and light bulbs, you may have come across the acronym CRI, usually accompanied by a number. CRI stands for Color Rendering Index. If you are serious about making your home or workspace look better, as well as the people in it, it’s a term you should understand. Read on for our easy-to-follow primer on CRI and why it’s important.
What CRI Means
First of all, do not confuse color rendering index with color temperature. Color temperature, measured in Kelvin, denotes how warm or cool lighting is. Warmer, yellowish temperatures are generally preferred to set a relaxing ambience, such as at a restaurant, while neutral or cooler temperatures tend to be better for tasks and work spaces in office, commercial, and industrial settings.
Although color temperature is important, your choice in that department depends largely on your personal taste and the space you will be illuminating. CRI, on the other hand, is generally less dependent on these variables. For most people and places, the higher the CRI, the better.
CRI refers to how accurately artificial light shows colors of the objects (or people) under them. Using a numerical scale from 1 to 100, CRI evaluates the color rendition and color accuracy of objects under different lights compared to how those objects would look under incandescent lights or natural sunlight. Technically speaking, incandescent lights and sunlight are considered “blackbody radiators” and have a perfect CRI score of 100…so they’re the benchmark. The higher the numerical value of CRI, the better the light fixture or bulb’s color rendition. Generally, a CRI of 80 or above is considered good, while a CRI of 90 or better is thought of as excellent. Think of CRI numbers as exam scores: 80s are Bs, while 90s are As.
Why CRI Is Important
Why is color rendition important? It can be a crucial factor in practically any space, from your home to your business. A lamp with a low CRI will impart a flat, washed-out hue to whatever it illuminates. In objects, this can mean drab, dull colors. In people, this can translate into sickly skin tones and unappealing, lifeless eyes.
Conversely, lighting with a high CRI can instill vibrant life in your environemnt. A high CRI will make the colors of furniture, clothing, food, and other objects “pop,” adding a deeply rich subtlety to the design tableau you have set. This flattering aspect carries over to people. High CRI will help give people a rich skin tone and a glowing, healthy look. A high CRI rating is especially important for color-critical applications and environments where visual appeal, presentation, and color accuracy is vital to business. This includes retail stores to highlight colorful clothing, grocery stores to make the food and produce look delicious, and even in real estate when making a home look vibrant and appealing will help it sell.
Why CRI Is Becoming More Important
In the era of incandescent light bulbs, CRI wasn’t such a big deal. That’s because incandescents deliver great color rendering.
That was before incandescent bulbs began to disappear from the lighting scene, largely because of their poor energy efficiency. At first, they were replaced by more energy-efficient fluorescent lamps. Now, LED bulbs are becoming a popular alternative to fluorescents.
LEDs have been lauded for their superior energy efficiency even compared to energy-stingy fluorescents. They also boast other benefits, such as longer life. In addition, they contain no hazardous mercury and do not shatter. So the lighting baton now is passing from fluorescents to LEDs.
LED Lights and CRI
Fortunately, LEDs boast one other crucial advantage over fluorescents. They can provide better CRI. That means you can enjoy more vibrant, realistic colors, whether you are shaving or putting on makeup in front of your bathroom mirror at home, illuminating art on a wall, or lighting a window display in a store.
Different types of light bulbs have different color-rendering abilities. At the bottom, for instance, are high-pressure sodium and mercury-vapor lights, with CRIs of about 24 and 49 respectively. Although no bulb can match the ideal color rendition of incandescents, some do a pretty good job. Fluorescent bulbs, for instance, can give decent CRI, although you have to pick and choose. Depending on coating, fluorescents have a CRI range of 50 to 85. When you pick the top fluorescents, you can get good but not great color rendition.
Modern LEDs, however, can boast CRIs into the high 90s. This means you can get nearly perfectly natural color if you choose a LED with a high CRI. This can be crucial in businesses where you are looking for attractive natural colors, such as restaurants or stores, or in homes where you want everyone to look and feel their best and your residence to look its best.
The best thing about LED lights with excellent, high CRI ratings is that they don’t cost much more than those with standard good CRI ratings. Considering the benefits of natural color rendition, it can pay in many ways to spend a little more for a higher CRI. Plus with the constant evolution of LED technology, LED performance keeps increasing and prices keep falling.
Credits: Take Three Lighting